1. Field of the Invention
The present invention relates generally to recovery of subterranean resources and more particularly to inducing fracture in geological structures by generation of pressure waves in a fluid medium in a borehole extending at least partially into the geological structures.
2. Description of the Related Art
Fracture of a region surrounding a borehole can allow for improved efficiency of oil recovery in certain types of formations. Conventionally, fracture in the geologic structure has been produced by generation of hydraulic pressure, which may be a static or quasi-static pressure generated in a fluid in the borehole. Another conventional method has included generation of a shock in conjunction with a hydraulic wave by creating an electrical discharge across a spark gap.